This invention relates to an airway humidifier for humidifying and delivering gases such as air or oxygen via a tube directly to a patient or other person needing breathing support.
In humidifiers used today, the air is typically overheated up to 50.degree. to 60.degree. C., and the cooling of the air as it proceeds to the person's airway depends on many factors, e.g. room temperature, length of the tube from the humidifier to the person, minute volume etc. Therefore, the temperature reaching the sensitive tissue of the airway is not well controlled. Often moisture is condensed in the tube leading to the patient and creates an accumulation that can cause harm. Furthermore, in present-day humidifiers there is direct contact between air and liquid water which is hygienically undesirable.
The invention constitutes an improvement over my prior patents U.S. Pat. Nos. 3,616,796; 3,871,373; 3,912,795 and to later efforts of Dobritz, U.S. Pat. Nos. 4,010,748 and 4,086,305. According to my prior patents, a new general type of airway humidifier for the respiratory tract is provided which operates according to the diffusion principle in which water vapor from a water supply permeates a wall or membrane and enters a stream of breathing air while the water supply is maintained separate from the air stream by the wall. Such a di-fusion humidifier offers a number of potential advantages over other methods of humidification, but no satisfactory form for its manufacture has yet been realized. The present invention fulfills this need.